Problem: A dirt bike shop sold $51$ tires today. At the end of the day, the store only has $11$ tires left. How many tires did the dirt bike shop have at the beginning of the day?
Explanation: To find the ${\text{total}}$ number of tires the store had to start with, we start with the number of ${\text{Tires sold}}$, and add the number of ${\text{Tires left over}}$. $?$ $51$ $11$ Total tires Tires sold Tires left ${51} + {11} = {\Box}$ Let's add to find the total number of tires. $$ $$ $$ $$ $$ $$ ${+}$ $$ $$ ${=}$ $$ $$ $$ $$ $$ $$ $$ ${51} + {11} = {62}$ The dirt bike shop had ${62}$ tires before the sale.